I find it amazing the extent to which we go to avoid brain strain.

Quite simply: People prefer the easiest route.

We want the simplest explanation, the easiest phone to use, and the obvious choice to be true. See, people are drawn to this simplicity in everything we do and say.

This is why simplicity is important in branding. And simplicity is also listed as a key tenant of persuasion.

Perhaps to avoid brain strain, people are acting in more of an automatic way than we think they are?

You see a coupon – and you do what it tells you to.

The extent to which we have learned to operate mechanically on that assumption is illustrated in the experience of one automobile-tire company. Mailed-out coupons that—because of a printing error—offered no savings to recipients produced just as much customer response as did error-free coupons that offered substantial savings. The obvious but instructive point here is that we expect discount coupons to do double duty. Not only do we expect them to save us money, we also expect them to save us the time and mental energy required to think about how to do it. In today’s world, we need the first advantage to handle pocketbook strain; but we need the second advantage to handle something potentially more important—brain strain.

-Robert Cialdini, Influence